Ag Precision Mapping and Section Control Software
QtAgOpenGPS is a direct port of Brian Tischler's [AgOpenGPS] (https://github.com/farmerbriantee/AgOpenGPS), which was originally written in C#. This port aims to follow AgOpenGPS closely, and not introduce any new algorithms or significant architecture modifications, except as required to work with Qt and C++. Currently it's not quite up to the latest commits on Brian's C# AOG, but nearly so.
Quoting the README.me for AgOpenGPS:
"This project is for my personal use only, and has no commercial value whatsoever. This software is not for sale, is incomplete, is in development to show concepts only and is mostly non functional. Any use of this software is not recommended and is intended for simulation only.
This software reads NMEA strings for the purpose of recording and mapping position information for Agricultural use. Also it has up to 8 Section Control to control implements application of product preventing over-application.
Also ouputs angle delta and distance from reference line for AB line and Contour guidance."
Eventually the other utilities in AOG will be ported, including the NMEA simulator.
This application is distributed here in source code form only. I will post demo binaries outside of this tree somewhere.
Much of the code is copied straight from the AOG C Sharp sources and is therefore copyright Brian Tischler. Everything else is copyright Michael Torrie (torriem@gmail.com) and Muhktimar (tamirscn@gmail.com).
AOG was originally licensed under the GPLv3, so this port was also licensed under the GPLv3. AOG has since been relicensed to the MIT license, which is still compatible with the GPLv3, so this project remains GPLv3 for now.
QtAOG requires Qt 5.9 or newer to build, on any Qt-supported platform that supports OpenGL ES 2 or newer, or DirectX on Windows.
This port is mainly for my own entertainment, to allow me to run AOG on Linux, including SBCs like the Raspberry Pi, or even Android.
This port is as close to a 1:1 transliteration of the C# code as possible, using Qt to drive the GUI, and C++ and Qt together to replace the C# GUI components. Being such a direct translation, the code has a very C# feel to it, even in C++. There are lots of classes that are only instantiated once, and the formgps.h is very large, and the coupling between the various classes is extremely tight. In fact there are a lot of forward references to the main FormGPS class. Since formgps.h is required by just about class in the project, changes to formgps.h require a rebuild of every single object file.
Some symbols like function names have been changed to lower case letter first, following the convention Qt uses, and is often common in C++. Capital first letters are reserved for class names. However most variables, functions, and methods, retain the AOG names, unless architectural differences require moving code into different sections. For example, the OpenGL code runs in a different thread than the main GUI loop, the logic to set UI state has been pulled out of the function that does the actual drawing. Also since QtQuick itself uses OpenGL heavily, there's no point in having an "intializeGL" routine; rather each time we draw the frame we have to set all the variables including the model view and perspective matrices. Of course in OpenGL ES we must manage those matrices ourselves anyway.
As of March 14, 2020, the backend code is tracking the v4 branch of AOG, current to the March 10, 2020 commit.
UI is still mostly non-present, but works with the built-in simulator, UDP data stream, or a serial port. For testing purposes, a job and field is automatically started, and a demo AB line is defined at 5 degrees.
Section lookahead isn't working quite right compared to AOG. Zero speed doesn't seem to be detected, and sometimes turning a section off while on Auto will cause the entire tool to turn off.
GL font drawing has issues.
Manual UTurn "buttons" aren't drawing